cmd/compile: emit error message on mismatch import path

Fixes #54542

Change-Id: I16cfb84fc54892923106d0a6f0b3ba810886d077
Reviewed-on: https://go-review.googlesource.com/c/go/+/596396
Auto-Submit: Cuong Manh Le <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: David Chase <[email protected]>
Reviewed-by: Than McIntosh <[email protected]>

src/cmd/compile/internal/noder/unified.go

@@ -7,6 +7,7 @@ package noder
 import (
 	"fmt"
 	"internal/pkgbits"
+	"internal/types/errors"
 	"io"
 	"runtime"
 	"sort"
@@ -403,7 +404,10 @@ func readPackage(pr *pkgReader, importpkg *types.Pkg, localStub bool) {
 		r := pr.newReader(pkgbits.RelocMeta, pkgbits.PublicRootIdx, pkgbits.SyncPublic)
 
 		pkg := r.pkg()
-		base.Assertf(pkg == importpkg, "have package %q (%p), want package %q (%p)", pkg.Path, pkg, importpkg.Path, importpkg)
+		if pkg != importpkg {
+			base.ErrorfAt(base.AutogeneratedPos, errors.BadImportPath, "mismatched import path, have %q (%p), want %q (%p)", pkg.Path, pkg, importpkg.Path, importpkg)
+			base.ErrorExit()
+		}
 
 		r.Bool() // TODO(mdempsky): Remove; was "has init"
 

test/fixedbugs/issue54542.go

@@ -0,0 +1,67 @@
+// run
+
+//go:build !js && !wasip1
+
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+)
+
+const aSrc = `package a
+
+func A() { println("a") }
+`
+
+const mainSrc = `package main
+
+import "a"
+
+func main() { a.A() }
+`
+
+var srcs = map[string]string{
+	"a.go":    aSrc,
+	"main.go": mainSrc,
+}
+
+func main() {
+	dir, err := os.MkdirTemp("", "issue54542")
+	if err != nil {
+		panic(err)
+	}
+	defer os.RemoveAll(dir)
+
+	for fn, src := range srcs {
+		if err := os.WriteFile(filepath.Join(dir, fn), []byte(src), 0644); err != nil {
+			panic(err)
+		}
+	}
+
+	if _, err := runInDir(dir, "tool", "compile", "-p=lie", "a.go"); err != nil {
+		panic(err)
+	}
+
+	out, err := runInDir(dir, "tool", "compile", "-I=.", "-p=main", "main.go")
+	if err == nil {
+		panic("compiling succeed unexpectedly")
+	}
+
+	if bytes.Contains(out, []byte("internal compiler error:")) {
+		panic(fmt.Sprintf("unexpected ICE:\n%s", string(out)))
+	}
+}
+
+func runInDir(dir string, args ...string) ([]byte, error) {
+	cmd := exec.Command("go", args...)
+	cmd.Dir = dir
+	return cmd.CombinedOutput()
+}